Frequency Diverse Array MIMO Radar Adaptive Beamforming with Range-Dependent Interference Suppression in Target Localization

Abstract

Conventional multiple-input and multiple-output (MIMO) radar is a flexible technique which enjoys the advantages of phased-array radar without sacrificing its main advantages. However, due to its range-independent directivity, MIMO radar cannot mitigate nondesirable range-dependent interferences. In this paper, we propose a range-dependent interference suppression approach via frequency diverse array (FDA) MIMO radar, which offers a beamforming-based solution to suppress range-dependent interferences and thus yields much better DOA estimation performance than conventional MIMO radar. More importantly, the interferences located at the same angle but different ranges can be effectively suppressed by the range-dependent beamforming, which cannot be achieved by conventional MIMO radar. The beamforming performance as compared to conventional MIMO radar is examined by analyzing the signal-to-interference-plus-noise ratio (SINR). The Cramér-Rao lower bound (CRLB) is also derived. Numerical results show that the proposed method can efficiently suppress range-dependent interferences and identify range-dependent targets. It is particularly useful in suppressing the undesired strong interferences with equal angle of the desired targets.

Development of frequency diverse array radar technology: a review

“…As the transmit/receive FDA pattern is range‐ambiguous and range dependent, a vertical FDA approach has been proposed to separate range‐ambiguous clutter in vertical frequency domain and then achieving clutter suppression in each separated region using STAP methods [64]. Another adaptive receive beamforming for MIMO‐FDA has been proposed in [65] to suppress the range‐dependent interferences for improved target localisation. Furthermore, a doubled pulsed MIMO‐FDA has been proposed in [66] for improved target localisation.…”

Cognitive FDA‐MIMO radar for LPI transmit beamforming

“…To identify the performance of FDA‐MIMO localisation, we briefly deviate the CRLBs of FDA‐MIMO as follows (refer to [35] for the details). By rewriting (2), we obtained: where Consequently, the unknown p...…”

“…To overcome this problem, the FDA and MIMO hybrid technique, namely FDA‐MIMO is proposed in [34], which jointly utilises the advantages of FDA in range‐dependent transmit beampattern and MIMO in increased degrees‐of‐freedom. In our earlier work [35], we investigated the FDA‐MIMO for suppressing range‐dependent interferences, which offers a beamforming‐based solution to suppress range‐dependent interferences and thus yields better direction of arrival estimation performance than conventional MIMO radar. More importantly, the interferences located at the same angle but different ranges can be effectively suppressed by the range‐dependent beamforming, which cannot be achieved by conventional phased‐array radars.…”

Cognitive MIMO Frequency Diverse Array Radar with High LPI Performance

“…Let s( ) be the vector collecting all these waveforms. The baseband equivalent model, in complexvalued form, of the transmitted signals from the th transmit element can be expressed as [29][30][31] ( , ) ( ) ,…”